First Online: 08 September 2006Received: 15 August 2006Accepted: 08 September 2006

Abstract

In the mid-1990-s, researchers hypothesized, based on new viral load data, that HIV-1 causes CD4 T-cell depletion by direct cytopathic effect. New data from non-human primate studies has raised doubts about this model of HIV-1 pathogenesis. Despite having high levels of viremia, most SIV infections are well tolerated by their natural hosts. Two recent studies of these models provide information, which may be useful in determining how HIV-1 causes CD4 T-cell loss. A full understanding of pathogenesis may lead to novel therapies, which preserve the immune system without blocking virus replication.

Electronic supplementary materialThe online version of this article doi:10.1186-1742-4690-3-60 contains supplementary material, which is available to authorized users.